Download Solving Humidity Problems Is No Sweat

Solving Humidity Problems Is No Sweat
By George Porter
Winter is here once again and we are confronted with the problem of having colder outside
weather meeting the warm heated air inside the home, resulting in condensation. In a previous
article, we discussed how site preparation can affect condensation and what were some of the
things we could do about that.
Site preparation is, however, not the only thing that can affect condensation. Even if it is the only
thing we can do about it as installers. Perhaps part of our job as installers is to educate the
consumer that all his problems may not lie with someone else. With that in mind, and because it’s
winter, I thought it would be good to talk about the problem.
First, a little background. Water comes in three stages. There’s liquid like the water you drink,
there’s ice like you put in the water you drink and water can also occur as a gas. It’s invisible,
you can’t smell it, but you can feel it. It’s known as humidity. As our friends in the South can
tell you, warm air holds a lot more humidity than cold air. The driest place on the face of the
earth is the South Pole and the wettest places on the face of the earth are jungles and such along
the Equator. Consequently, if you would take some of the air out of the jungle and put it at the
South Pole, the water would have to go, because it could not hold it as the temperature changed.
As the humidity leaves the air in the form of a gas, it turns into liquid, and if it’s cold enough,
that liquid will then turn to ice. That’s what happened to all the water at the South Pole.
Whenever they do happen to get some in the air it winds up on the ground in the form of snow.
It doesn’t take these kinds of extremes to produce a similar reaction in a manufactured house.
Humidity and condensation are natural occurrences and have nothing to do with the structure of
the house, manufactured or otherwise. Air can only hold a limited amount of water vapor
depending on its temperature. When air is holding half as much water as it could possibly hold at
a certain temperature, it is said to have 50% humidity. When air is holding 100% of all the water
it could possibly hold at a certain temperature, it is said to be at 100% humidity. When the
moisture in the air tries to exceed 100% humidity, it changes back into a liquid and appears as
steam or condensation.
There are two ways to change this relative humidity. ir’s ability to hold water is relative to its
temperature hence the term relative humidity. You can increase the relative humidity by simply
increasing the water in the air or by lowering the temperature. When you exhale on a cold day, the
warm moist air in your lungs leaves your mouth and forms a little cloud. Because the cold air
your breath is entering will not hold so much water, the excess moisture is transformed into
vapor in front of your face. This same moisture can form on any cold surface. If you have a cold
glass of water in a warm house, it will begin to sweat and drip as a result of moist air touching the
colder layer of air very close to the glass.
All of these will happen inside any home. The sweating and water running down the windows is
actually a safety gauge. It’s telling you that there is an excessive amount of moisture in the home
and that you must lower the humidity. The same thing that’s happening on your windows can be
happening inside your walls and roof and every other part of your house. It can cause warp, rot,
mildew, paint failure C in general, do severe damage to the home.
There was a time when our industry was not bothered by this problem. Some of the early
examples of our industry always seemed to have a little breeze blowing through them, summer or
winter. When you had large amounts of outside air infiltrating throughout the home, it was
virtually impossible to trap any moisture laden air within the home. Since those early years,
however, our industry has done a fantastic job in thoroughly weatherproofing and sealing our
housing. Our homes are extremely tight as evidenced by the mandatory air exchange systems
found in many houses today. We were the first type of housing that was required to have outside
air going into the fireplace so that it wouldn’t suffocate the people in the house by burning up all
the oxygen.
All of this produces very low heat bills, but it also allows us to develop our own mini
environment inside the house and it is that environment that must be controlled. Only the
homeowner can do it because it is his lifestyle and habits that will determine the humidity within
the home. Listed below are some activities and the amount of water they put in the air in your
home if you do not use an exhaust fan or vent the home in any way:
Washing dishes
Warm baths and showers
Hot and steamy baths and showers
Mopping floors
Boiling foods
Unvented clothes dryer
Kerosene heaters
Human breathing
1 pint
1 pint
1 pint
2 pints
2 pints
3 to 5 pints per load
4 pints per gallon of kerosene burned
1 pint per hour per person
Other sources of water could be house plants, aquariums and anything else that allows water to
evaporate. If we keep adding water from these sources on a daily basis and never remove it, the
home will be destroyed. In fact, the average family of four can easily add a 150 lbs. or more than
18 gallons of water per week to the air in the home. All of this moisture must eventually escape.
The safety gauge would be how much water you see condensating on your windows. A better
gauge would be a humidity gauge easily purchased at most hardware or department stores. DO
NOT USE a portable kerosene heater to warm the home. The expense of the problems caused by
the excessive humidity (4-1/2 pints per gallon) far exceed whatever savings, if any, can be
obtained over running the heater that came with the home. Put lids on pans when water is boiling
in them. Use the exhaust fan in the kitchen when cooking. Always use the exhaust fan when you
are taking a shower, or open the bathroom window. Open a few windows in the house every day
for a minute or two, even if the air outside is very cold. If you air out your home in this manner,
it will not only bring fresh air in the home, but it will also quickly lower the humidity inside the
house. If all else fails, the customer will have to purchase and use a dehumidifier. If the installer
has placed the 6 mm of polyethylene on the ground beneath the home as recommended by the
manufacturer of the home and has properly vented the skirting, he has done everything he can
possibly do to help alleviate this problem. The rest has to be left up to the customer. The best
thing we can do as installers is be absolutely sure that the customer is aware of this C hopefully
before he gets the problem. Many companies and manufacturers of windows publish pamphlets
on condensation. If you live in an area prone to the problem, please be sure that one of these
brochures is lying in the house or presented to the customer at settlement. If he says he never had
this problem in any other house he ever had, tell him that he may never have had a house built as
tightly and installed as precisely as the one he now owns. And the fact that we have these
problems is the proof.